A microwave oscillator having a Gunn diode is disclosed, for example, by German Patent No. DE 28 26 767 B2 or by German Published Unexamined Application No. DE-OS 27 09 210. This related art describes arranging the adjustment pin either in the narrow side or in the wide side of the waveguide supporting the Gunn diode. Thus, in the one case, the adjustment pin is aligned vertically and, in the other case, parallel to the coupling pin feeding the supply voltage to the Gunn diode. Usually, in a microwave oscillator of this kind, the short-circuiting wall of the waveguide is movable, so that the possibility of tuning the oscillator frequency with inductive action is given. This tuning action mainly has an effect on the power output by the oscillator. The adjustment pin that feeds the supply voltage to the Gunn diode is provided in the feed-through orifice to the waveguide with a stop filter (choke), to prevent any oscillator power from leaking off unintentionally through the feed-through orifice.
The object of the present invention is to devise a microwave oscillator whose frequency adjustment will be able to be carried out as simply as possible.